Model for microfiltration of poly-disperse suspensions
OwnerGeorges Belfort, Gautam Baruahinventors
Life of this patent
Estimating the term…
Abstract
The present invention relates to a method for predicting pressure independent permeation flux and target molecule yield in a permeate resulting from crossflow filtration of particles in a poly-disperse suspension, a method for determining packing density of particles at the membrane wall of a poly-dissperse suspension, a method for designing a filtration system for a poly-disperse suspension, a method of selecting operating conditions of a crossflow filtration system for poly-disperse suspensions, and a method of modeling a process for filtration of a poly-disperse suspension using a computer generated program for predicting pressure indendent permeation flux and taret molecule yield.
Claims79
A method for predicting pressure independent permeation flux and target molecule yield in a permeate resulting from crossflow membrane filtration of particles in a poly-disperse suspension, said method comprising:
- determining particle size distribution of the poly-disperse suspension;
- determining equivalent spherical radii of the particles;
- determining viscosity of the suspension;
- determining maximum back-transport velocity (ui) for all particles;
- estimating maximum aggregate packing volume fraction (φM) for all particles at a wall of the filtration membrane from geometric considerations;
- selecting the particle that gives a minimum permeation flux at a given filtration membrane shear rate, wherein the selected particle has a radius (αi);
- determing a predicted permeation flux (J);
- determining packing density φwi at a membrane wall for each particle size (αj for j≠i) at the predicted permeation flux;
- determining interstitial packing density (φwiinterstice) of particles in the suspension which are the smallest;
- determining minimum pore diameter (2rminimum) based on the packing density of each particle;
- and
- estimating yield of a target species in the filtration permeate by calculating observed sieving coefficient (So) for the target species, thereby predicting permeation flux and target molecule yield of the poly-disperse suspension during crossflow filtration.
A method for determining packing density of particles of a poly-disperse suspension at a membrane wall, said method comprising:
- providing a predicted permeation flux (J);
- determining packing density for all particle sizes at the predicted permeation flux;
- and
- determining interstitial packing density (φwiinterstice) of particles in the suspension which are smallest, thereby determining packing density at the membrane wall of particles of the poly-disperse suspension.
A method for predicting pressure independent permeation flux for crossflow membrane filtration of a poly-disperse suspension, said method comprising:
- determining viscosity of the suspension;
- determining maximum back-transport velocity (ui) for all particles;
- estimating maximum aggregate packing volume fraction (φM) for all particles at a wall of the filtration membrane from geometric considerations;
- selecting the particle that gives a minimum permeation flux at a given filtration membrane shear rate, wherein the selected particle has a radius (αi);
- determining a predicted permeation flux (J);
- and
- determining packing density (φwj) at the membrane wall for each particle size (αj for j≠i) at the predicted permeation flux, thereby predicting pressure independent permeation flux for the suspension.
A method for calculating yield of a target molecule in a permeate for a poly-disperse suspension during crossflow membrane filtration, said method comprising:
- determining minimum pore diameter (2rminimum) based on the packing density of each particle and
- estimating yield of a target species in the filtration permeate by calculating observed sieving coefficient (So) for the target species.
Dependencies are inferred from the claim text.